Question 1

Which of the following statements is TRUE?

Accepted Answer

A) PRPP is an effective feedback inhibitor of nucleotide synthesis. 
B) GTP serves as the energy input for AMP synthesis from IMP. 
C) Oxidation of ribosyl moieties to produce deoxynucleotides occurs at the diphosphate level. 
D) Thymidylate synthase methylates dUTP to produce dTTP. 
E) All of the above are true. 
A) PRPP is an effective feedback inhibitor of nucleotide synthesis. 
B) GTP serves as the energy input for AMP synthesis from IMP. 
C) Oxidation of ribosyl moieties to produce deoxynucleotides occurs at the diphosphate level. 
D) Thymidylate synthase methylates dUTP to produce dTTP. 
E) All of the above are true.

Question 2

Which of the following sequences for uric acid catabolism is correct for marine invertebrates?

Accepted Answer

A) uric acid $\to$allantoin$\to$allantoic acid$\to$urea$\to$NH4+ 
B) uric acid $\to$ allantoic acid$\to$urea$\to$NH4+ 
C) uric acid $\to$allantoin$\to$ urea$\to$NH4+ 
D) uric acid $\to$allantoin$\to$allantoic acid$\to$urea 
E) none of the above 
A) uric acid $\to$allantoin$\to$allantoic acid$\to$urea$\to$NH4+ 
B) uric acid $\to$ allantoic acid$\to$urea$\to$NH4+ 
C) uric acid $\to$allantoin$\to$ urea$\to$NH4+ 
D) uric acid $\to$allantoin$\to$allantoic acid$\to$urea 
E) none of the above

Question 3

Individuals that do not consume adequate folic acid have serious problems with the

Accepted Answer

A) synthesis of dATP. 
B) synthesis of dCTP. 
C) synthesis of dGTP. 
D) synthesis of dTTP. 
E) all of the above 
A) synthesis of dATP. 
B) synthesis of dCTP. 
C) synthesis of dGTP. 
D) synthesis of dTTP. 
E) all of the above

Question 4

The end products of pyrimidine catabolism are

Accepted Answer

A) "uric acid and glyoxylic acid." 
B) "uric acid and allantoin." 
C) "$\beta$-alanineand $\beta$-aminoisobutyrate." 
D) "$\beta$-alanine and $\alpha$-ketoglutarate." 
E) "none of the above" 
A) "uric acid and glyoxylic acid." 
B) "uric acid and allantoin." 
C) "$\beta$-alanineand $\beta$-aminoisobutyrate." 
D) "$\beta$-alanine and $\alpha$-ketoglutarate." 
E) "none of the above"

Question 5

Which of the following statements about nucleotide synthesis is (are)true?
(I)Most dietary nucleotides are salvaged and used in DNA synthesis.
(II)Most nucleotides in cells are from de novo pathways.
(III)Most nucleotides in cells are salvaged and used in RNA synthesis.

Accepted Answer

A) I,II 
B) I only 
C) II only 
D) II,IV 
E) III only 
A) I,II 
B) I only 
C) II only 
D) II,IV 
E) III only

Question 6

The first step in pyrimidine biosynthesis is the formation of

Accepted Answer

A) carbamoyl phosphate. 
B) carbamoyl aspartate. 
C) β-aminoisobutyrate. 
D) dihydroorotate. 
E) none of the above 
A) carbamoyl phosphate. 
B) carbamoyl aspartate. 
C) β-aminoisobutyrate. 
D) dihydroorotate. 
E) none of the above

Question 7

Which of the choices correctly represents the synthesis of dTTP as represented by the following reactions?
(I)dUMP + N5,N10-methylenetetrahydrofolate $\to$ dTMP + dihydrofolate
(II)dTMP + ATP $\to$ dTTP + Pi
(III)dUTP + H2O $\to$ dUMP + PPi
(IV)dUTP + N5,N10-methylenetetrahydrofolate $\to$ dTTP + dihydrofolate

Accepted Answer

A) I $\to$ II $\to$ IV 
B) IV only 
C) III $\to$ IV $\to$ I $\to$ II 
D) III $\to$ I $\to$ II 
E) III $\to$ I 
A) I $\to$ II $\to$ IV 
B) IV only 
C) III $\to$ IV $\to$ I $\to$ II 
D) III $\to$ I $\to$ II 
E) III $\to$ I

Question 8

Matching
Choose the correct answer from the list.Not all the answers will be used.

-Purines are degraded to ______.

Accepted Answer

A)  fumarate 
B)  NADPH 
C)  salvage 
D)  uric acid 
E)  oxidation
F) XMP
G) iron
H) allopurinol
I) IMP
J) Oxidation
K) therapeutic
L) suicide
M) molybdenum
N) FADH
O) Malonyl-CoA
P) reduction
Q) antifolate 
A)  fumarate 
B)  NADPH 
C)  salvage 
D)  uric acid 
E)  oxidation
F) XMP
G) iron
H) allopurinol
I) IMP
J) Oxidation
K) therapeutic
L) suicide
M) molybdenum
N) FADH
O) Malonyl-CoA
P) reduction
Q) antifolate

Question 9

Ribonecleotides   Using the diagram above,answer questions 43 - 45.C may be used to represent either or both of the atoms labeled C.
-Glycine contributes to the ring at position _____.

Accepted Answer

A) A 
B) B 
C) C 
D) D 
E) E 
A) A 
B) B 
C) C 
D) D 
E) E

Question 10

Myoadenylate deaminase deficiency is most evident in ______ tissue.

Accepted Answer

A) liver 
B) connective 
C) neural 
D) muscle 
E) brain 
A) liver 
B) connective 
C) neural 
D) muscle 
E) brain

Question 11

The proposed mechanism of the Class I RNR involves

Accepted Answer

A) electron transfer directly from substrate to tyrosine 122. 
B) electron transfer from substrate to various cysteine residues. 
C) an exposed tyrosine which accepts an electron from the ribosyl radical. 
D) electron donation to external reducing agents. 
E) none of the above 
A) electron transfer directly from substrate to tyrosine 122. 
B) electron transfer from substrate to various cysteine residues. 
C) an exposed tyrosine which accepts an electron from the ribosyl radical. 
D) electron donation to external reducing agents. 
E) none of the above

Question 12

Which of the following reactions is NOT catalyzed by nucleoside diphosphate kinase?

Accepted Answer

A) GDP + ATP $\to$ GTP + ADP 
B) UDP + ATP $\to$  UTP + ADP 
C) CDP + ATP $\to$  CTP + ADP 
D) dGDP + ATP $\to$  dGTP + ADP 
E) It catalyzes all the above. 
A) GDP + ATP $\to$ GTP + ADP 
B) UDP + ATP $\to$  UTP + ADP 
C) CDP + ATP $\to$  CTP + ADP 
D) dGDP + ATP $\to$  dGTP + ADP 
E) It catalyzes all the above.

Question 13

Matching
Choose the correct answer from the list.Not all the answers will be used.

-______ compounds are effective anticancer agents.

Accepted Answer

A)  fumarate 
B)  NADPH 
C)  salvage 
D)  uric acid 
E)  oxidation
F) XMP
G) iron
H) allopurinol
I) IMP
J) Oxidation
K) therapeutic
L) suicide
M) molybdenum
N) FADH
O) Malonyl-CoA
P) reduction
Q) antifolate 
A)  fumarate 
B)  NADPH 
C)  salvage 
D)  uric acid 
E)  oxidation
F) XMP
G) iron
H) allopurinol
I) IMP
J) Oxidation
K) therapeutic
L) suicide
M) molybdenum
N) FADH
O) Malonyl-CoA
P) reduction
Q) antifolate

Question 14

What category of reaction converts orotate monophosphate (OMP)into uracil monophosphate (UMP)?

Accepted Answer

A) a transamination 
B) a methylation 
C) a decarboxylation 
D) a carboxylation 
E) none of the above 
A) a transamination 
B) a methylation 
C) a decarboxylation 
D) a carboxylation 
E) none of the above

Question 15

Matching
Choose the correct answer from the list.Not all the answers will be used.

-Deoxyribonucleotides are synthesized by ______ of the corresponding ribonucleotide's 2' carbon.

Accepted Answer

A)  fumarate 
B)  NADPH 
C)  salvage 
D)  uric acid 
E)  oxidation
F) XMP
G) iron
H) allopurinol
I) IMP
J) Oxidation
K) therapeutic
L) suicide
M) molybdenum
N) FADH
O) Malonyl-CoA
P) reduction
Q) antifolate 
A)  fumarate 
B)  NADPH 
C)  salvage 
D)  uric acid 
E)  oxidation
F) XMP
G) iron
H) allopurinol
I) IMP
J) Oxidation
K) therapeutic
L) suicide
M) molybdenum
N) FADH
O) Malonyl-CoA
P) reduction
Q) antifolate

Question 16

Hydroxylation of IMP to form GMP occurs in conjunction with the ________ of _______.

Accepted Answer

A) oxidation;NADH 
B) reduction;NAD+ 
C) oxidation;NADPH 
D) reduction;NADP+ 
E) none of the above 
A) oxidation;NADH 
B) reduction;NAD+ 
C) oxidation;NADPH 
D) reduction;NADP+ 
E) none of the above

Question 17

The disease gout is characterized by high levels of ____,which forms crystal deposits in joints and is treated by inhibition of _______.

Accepted Answer

A) uric acid;urate oxidase 
B) uric acid;xanthine oxidase 
C) urea;urate oxidase 
D) xanthine;xanthine oxidase 
E) none of the above 
A) uric acid;urate oxidase 
B) uric acid;xanthine oxidase 
C) urea;urate oxidase 
D) xanthine;xanthine oxidase 
E) none of the above

Question 18

Which of the following correctly describes the formation of CTP?

Accepted Answer

A) UTP + Glutamine + ATP + H2O $\to$ Glutamate + ADP + Pi + CTP 
B) UMP + ATP + H2O + Glutamine $\to$ CMP + Glutamate + ADP + Pi 
C) TTP + N5,N10-Methylenetetrahydrofolate $\to$ CTP + Dihydrofolate 
D) UMP + Glutamine $\to$ Glutamate + CTP 
E) CMP + Glutamine + ATP $\to$ CTP + Glutamate + ADP + Pi 
A) UTP + Glutamine + ATP + H2O $\to$ Glutamate + ADP + Pi + CTP 
B) UMP + ATP + H2O + Glutamine $\to$ CMP + Glutamate + ADP + Pi 
C) TTP + N5,N10-Methylenetetrahydrofolate $\to$ CTP + Dihydrofolate 
D) UMP + Glutamine $\to$ Glutamate + CTP 
E) CMP + Glutamine + ATP $\to$ CTP + Glutamate + ADP + Pi

Question 19

Matching
Choose the correct answer from the list.Not all the answers will be used.

-Gout is treated using the compound ______.

Accepted Answer

A)  fumarate 
B)  NADPH 
C)  salvage 
D)  uric acid 
E)  oxidation
F) XMP
G) iron
H) allopurinol
I) IMP
J) Oxidation
K) therapeutic
L) suicide
M) molybdenum
N) FADH
O) Malonyl-CoA
P) reduction
Q) antifolate 
A)  fumarate 
B)  NADPH 
C)  salvage 
D)  uric acid 
E)  oxidation
F) XMP
G) iron
H) allopurinol
I) IMP
J) Oxidation
K) therapeutic
L) suicide
M) molybdenum
N) FADH
O) Malonyl-CoA
P) reduction
Q) antifolate

Question 20

Which best describes the synthesis of purine nucleotides?

Accepted Answer

A) The basic ring structure,orotate,is synthesized and then linked to PRPP.This is then modified to produce either GMP or AMP. 
B) The basic ring structure,inosine,is synthesized and then linked to PRPP.This is then modified to produce either GMP or AMP. 
C) The basic ring structure,orotate,is synthesized stepwise on PRPP.This is then modified to produce either GMP or AMP. 
D) The basic ring structure,inosine,is synthesized stepwise on PRPP.This is then modified to produce either GMP or AMP. 
E) The basic ring structure,orotate,is synthesized and then linked to PRPP.This is then modified to produce either UMP or CMP. 
A) The basic ring structure,orotate,is synthesized and then linked to PRPP.This is then modified to produce either GMP or AMP. 
B) The basic ring structure,inosine,is synthesized and then linked to PRPP.This is then modified to produce either GMP or AMP. 
C) The basic ring structure,orotate,is synthesized stepwise on PRPP.This is then modified to produce either GMP or AMP. 
D) The basic ring structure,inosine,is synthesized stepwise on PRPP.This is then modified to produce either GMP or AMP. 
E) The basic ring structure,orotate,is synthesized and then linked to PRPP.This is then modified to produce either UMP or CMP.

Exam 23: Nucleotide Metabolism

Which of the following statements is TRUE?

Which of the following sequences for uric acid catabolism is correct for marine invertebrates?

Individuals that do not consume adequate folic acid have serious problems with the

The end products of pyrimidine catabolism are

Which of the following statements about nucleotide synthesis is (are)true? (I)Most dietary nucleotides are salvaged and used in DNA synthesis. (II)Most nucleotides in cells are from de novo pathways. (III)Most nucleotides in cells are salvaged and used in RNA synthesis.

The first step in pyrimidine biosynthesis is the formation of

Matching Choose the correct answer from the list.Not all the answers will be used. -Purines are degraded to ______.

Ribonecleotides Using the diagram above,answer questions 43 - 45.C may be used to represent either or both of the atoms labeled C. -Glycine contributes to the ring at position _____.

Myoadenylate deaminase deficiency is most evident in ______ tissue.

The proposed mechanism of the Class I RNR involves

Which of the following reactions is NOT catalyzed by nucleoside diphosphate kinase?

Matching Choose the correct answer from the list.Not all the answers will be used. -______ compounds are effective anticancer agents.

What category of reaction converts orotate monophosphate (OMP)into uracil monophosphate (UMP)?

Matching Choose the correct answer from the list.Not all the answers will be used. -Deoxyribonucleotides are synthesized by ______ of the corresponding ribonucleotide's 2' carbon.

Hydroxylation of IMP to form GMP occurs in conjunction with the ________ of _______.

The disease gout is characterized by high levels of ____,which forms crystal deposits in joints and is treated by inhibition of _______.

Which of the following correctly describes the formation of CTP?

Matching Choose the correct answer from the list.Not all the answers will be used. -Gout is treated using the compound ______.

Which best describes the synthesis of purine nucleotides?

Introduction to the Chemistry of Life

Water

Nucleotides, nucleic Acids, and Genetic Information

Amino Acids

Proteins: Primary Structure

Proteins: Three-Dimensional Structure

Protein Function Part I: Myoglobin and Hemoglobin

Carbohydrates

Lipids and Biological Membranes

Membrane Transport

Enzyme Catalysis

Enzyme Kinetics, inhibition and Control

Biochemical Signaling

Introduction to Metabolism

Glucose Catabolism

Glycogen Metabolism and Gluconeogenesis

Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Mammalian Fuel Metabolism: Integration and Regulation

Nucleic Acid Structure

DNA Replication, repair and Recombination

Transcription and Rna Processing

Protein Synthesis

Regulation of Gene Expression

Filters

Hydroxylation of IMP to form GMP occurs in conjunction with the __ of _.

The disease gout is characterized by high levels of ,which forms crystal deposits in joints and is treated by inhibition of ___.